Prove the Identity $$\cos \left( x + \frac { \pi } { 2 } \right) = - \sin x$$

question 6

Essay

Prove the identity.
- $$\cos \left( x + \frac { \pi } { 2 } \right) = - \sin x$$

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Definitions:

Bookkeeping

The process of recording financial transactions and maintaining financial records for a business, ensuring accuracy in accounting for income, expenses, assets, and liabilities.

African Methodist Episcopal Church

The first independent Protestant denomination to be founded by black people, established in Philadelphia in 1816.

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A minister, educator, and writer who founded the African Methodist Episcopal Church in 1816, the first independent black denomination in the United States.

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A prominent African-American abolitionist, author, and orator in the 19th century, known for his efforts to end slavery and his advocacy for civil rights.